dst – output image of the same size and the same number of channels as src.

ddepth – desired depth of the destination image; if it is negative, it will be the same as src.depth(); the following combinations of src.depth() and ddepth are supported:

src.depth() = CV_8U, ddepth = -1/CV_16S/CV_32F/CV_64F

src.depth() = CV_16U/CV_16S, ddepth = -1/CV_32F/CV_64F

src.depth() = CV_32F, ddepth = -1/CV_32F/CV_64F

src.depth() = CV_64F, ddepth = -1/CV_64F

when ddepth=-1, the output image will have the same depth as the source.

kernel – convolution kernel (or rather a
correlation kernel), a single-channel floating point matrix; if you want
to apply different kernels to different channels, process them individually.

anchor – anchor of the kernel that indicates the
relative position of a filtered point within the kernel; the anchor
should lie within the kernel; default value (-1,-1) means that the
anchor is at the kernel center.

delta – optional value added to the filtered pixels before storing them in dst.